Plate Umpire position between innings (NFHS)

[KJUmp]

Originally Posted by HugoTafurst

I believe it is not up for "adoption", but an NFHS required mechanic.

Local HS umpiring boards or state associations are free to adopt whatever NFHS mechanics they choose to. They're free to decide where (and for what reason) they want their umpires to position themselves between innings.
As an example (from another sport), in HS basketball, it has been reported on the basketball forum that any number of local boards and state associations (mine included) have chosen to NOT adopt the new NFHS mechanic of having the trail official tableside after a foul has been reported.